I am a Tableau Desktop user (no access to Tableau Server at this time). Is it possible for me to embed a dashboard directly into SharePoint without Server? I am seeing several questions on this topic, but none of them marked answered.

Without Tableau Server, your options are limited. You could publish to Tableau Public then embed your workbook, but that would make the workbook visible to everyone in the world. Otherwise, I don't think you have any options.